Standardized Visual Defect Classification Methods for Greige Cloth Inspection
Standardized greige inspection combines calibrated D65 illumination and 4-point scoring to convert visual cloth defects into precise commercial deductions.
Weft Loops
Insertion Defect
Unintended slackness in the transverse yarn path during loom insertion leaves raised loops of yarn protruding from the surface or edge of the fabric. The fault designated as weft loops occurs when filling yarn snags, kinks, or fails to maintain continuous tension as it traverses the warp shed, causing excess yarn to bunch into small circular ridges in the finished linen cloth. This defect compromises surface flatness and creates visible blemishes in fine linen apparel and bedding fabrics.
Mechanical Origins
Inadequate filling brake tension on the pre-winder allows the stiff flax yarn to spring loose during the insertion phase. When rapier grippers transfer the filling at the center of the shed, poor clamp timing or accumulated flax lint in the gripper jaws can release the yarn prematurely. Static electricity and excessive yarn hairiness cause the inserted filling to cling to adjacent warp ends, preventing full extension across the fabric width before beat-up.
Loom technicians resolve this condition by adjusting electronic filling brake pressure, blowing lint from rapier heads, and regulating shed opening timing.
Grading Penalties
Perch inspection tables detect raised loops through oblique surface lighting during final quality grading. Under standard fabric inspection rules, each prominent loop receives a penalty of two to four demerit points depending on its length and location within the cuttable width. Rolls containing clusters of filling loops are rejected or downgraded to commercial seconds during final quality auditing.